Bug#1150085: fortran-caffeine: FTBFS: flang-22: error: linker command failed with exit code 1 (use -v to see invocation)

[Santiago Vila]

Package: src:fortran-caffeine
Version: 0.8.0-1
Severity: serious
Tags: ftbfs forky sid

Dear maintainer:

During a rebuild of all packages in unstable, this package failed to build.

Below you will find the last part of the build log (probably the most
relevant part, but not necessarily). If required, the full build log
is available here:

https://people.debian.org/~sanvila/build-logs/202610/

About the archive rebuild: The build was made on virtual machines from AWS,
using sbuild and a reduced chroot with only build-essential packages.

If you cannot reproduce the bug please contact me privately, as I
am willing to provide ssh access to a virtual machine where the bug is
fully reproducible.

If this is really a bug in one of the build-depends, please use
reassign and add an affects on src:fortran-caffeine, so that this is still
visible in the BTS web page for this package.

Thanks.

--------------------------------------------------------------------------------
[...]
flang-22: error: linker command failed with exit code 1 (use -v to see invocation)
[ 79%]                          hello  done.

/usr/bin/x86_64-linux-gnu-ld.bfd: /usr/lib/x86_64-linux-gnu/libmpi.so: undefined reference to symbol 'ompi_mpi_byte'
/usr/bin/x86_64-linux-gnu-ld.bfd: /usr/lib/x86_64-linux-gnu/libopen_mpi.so.40: error adding symbols: DSO missing from command line
flang-22: error: linker command failed with exit code 1 (use -v to see invocation)
<ERROR> Compilation failed for object " hello "
<ERROR> stopping due to failed compilation
STOP 1
+ set +x
Defect reporting information:
--------------------------------------------------
Version info:
Caffeine version = "0.8.0"
external-modules = [ "assert_m" ]
link = ["gasnet-ibv-seq", "ibverbs", "hwloc", "pthread", "m", "assert", "mpi"]
--------------------------------------------------
Platform info:
Linux sbuild 6.12.111+deb13-cloud-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.12.111-1 (2026-09-28) x86_64 GNU/Linux
PRETTY_NAME="Debian GNU/Linux forky/sid"
NAME="Debian GNU/Linux"
VERSION_CODENAME=forky
--------------------------------------------------
Install settings:
ID=Mon Oct  5 11:12:45 UTC 2026 sbuild
PREFIX=/<<PKGBUILDDIR>>/build-flang-22-ibv
FPM=/usr/bin/fpm
FC=/usr/lib/llvm-22/bin/flang-new
CC=/usr/bin/clang-22 -std=gnu23 -g -Werror=implicit-function-declaration -ffile-prefix-map=/buildroot=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection
FFLAGS=-g -O3 -DASSERT_MULTI_IMAGE -DASSERT_PARALLEL_CALLBACKS -DHAVE_MULTI_IMAGE_SUPPORT -DJULIENNE_PARALLEL_CALLBACKS -DASSERTIONS -DCAF_NETWORK_IBV -D_FORTIFY_SOURCE=2 -cpp -I./include -I/usr/lib/x86_64-linux-gnu/fortran/flang-mod-22 -I/usr/include
CFLAGS=-g -O3 -DASSERT_MULTI_IMAGE -DASSERT_PARALLEL_CALLBACKS -DHAVE_MULTI_IMAGE_SUPPORT -DJULIENNE_PARALLEL_CALLBACKS -DASSERTIONS -DCAF_NETWORK_IBV -D_FORTIFY_SOURCE=2 -cpp -I./include -I/usr/lib/x86_64-linux-gnu/fortran/flang-mod-22 -I/usr/include
LDFLAGS=-D_GNU_SOURCE=1 -L/usr/lib/x86_64-linux-gnu -L/usr/lib/x86_64-linux-gnu/fortran/flang -lmpi
link = ["gasnet-ibv-seq", "ibverbs", "hwloc", "pthread", "m", "assert", "mpi"]
GASNET=/usr/lib
GASNET_CONDUIT=ibv
GASNET_THREADMODE=seq
--------------------------------------------------
FPM : /usr/bin/fpm
-rwxr-xr-x 1 root root 11868728 May  5 12:12 /usr/bin/fpm
-rwxr-xr-x 1 root root 12M May  5 12:12 /usr/bin/fpm
Version:     0.13.0, alpha
Program:     fpm(1)
Description: A Fortran package manager and build system
Home Page:   https://github.com/fortran-lang/fpm
License:     MIT
OS Type:     Linux
--------------------------------------------------
FC : /usr/lib/llvm-22/bin/flang-new
lrwxrwxrwx 1 root root 5 Jul 19 21:57 /usr/lib/llvm-22/bin/flang-new -> flang
-rwxr-xr-x 1 root root 48M Jul 19 21:57 /usr/lib/llvm-22/bin/flang-new
Debian flang version 22.1.8 (1+b2)
Target: x86_64-pc-linux-gnu
Thread model: posix
InstalledDir: /usr/lib/llvm-22/bin
--------------------------------------------------
CC : /usr/bin/clang-22 -std=gnu23 -g -Werror=implicit-function-declaration -ffile-prefix-map=/buildroot=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection
lrwxrwxrwx 1 root root 24 Jul 19 21:57 /usr/bin/clang-22 -> ../lib/llvm-22/bin/clang
-rwxr-xr-x 1 root root 131K Jul 19 21:57 /usr/bin/clang-22
Debian clang version 22.1.8 (1+b2)
Target: x86_64-pc-linux-gnu
Thread model: posix
InstalledDir: /usr/lib/llvm-22/bin
--------------------------------------------------

Oh no, the Caffeine build appears to have failed!
Please paste the ENTIRE output above into a new issue here:
   https://github.com/berkeleylab/caffeine/issues
make[1]: *** [debian/rules:52: override_dh_auto_build] Error 1
make[1]: Leaving directory '/<<PKGBUILDDIR>>'
make: *** [debian/rules:10: binary] Error 2
dpkg-buildpackage: error: debian/rules binary subprocess failed with exit status 2
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